WO1989012596A1

WO1989012596A1 - Sorting apparatus having laterally tiltable trays

Info

Publication number: WO1989012596A1
Application number: PCT/DK1989/000153
Authority: WO
Inventors: Axel Møller KNUDSEN
Original assignee: Kosan Crisplant A/S
Priority date: 1988-06-21
Filing date: 1989-06-20
Publication date: 1989-12-28
Also published as: DK337788A; AU3860289A; DK337788D0

Abstract

In order to achieve that the transport trays (4) on a sorting conveyer can be tilted laterally for unloading goods to a selected receiving station along the conveyer, traditionally quite complicated and expensive mechanisms are used. The invention provides an extremely simple tilting mechanism, where each transport tray (4) is only supported by a rotation bearing joint (6, 8) having its axis of rotation oriented obliquely upwardly-forwardly or upwardly-rearwardly to the direction of transport. A lateral tilting of the horizontal tray (4) to one or the other side can then take place solely by a rotation actuation of the portion (6) of the bearing joint connected to the tray, and the bearing joint can then in a very simple manner be constituted by a pipe (6) which protrudes obliquely downwardly from the tray and is received on a fixed pivot (8) protruding obliquely upwardly from the conveyer chain.

Description

Sorting apparatus having laterally tiltable trays

The present invention relates to a sorting conveyer of the type defined in the introductory clause of claim 1. A conveyer of said type is known from DK-B-145,662, where each of said pivot shafts is carried through a bearing, which by means of a fixed supporting bracket on the chain is mounted in an oblique position spaced above the chain, the lower end of the pivot shaft just below said bearing being connected through a universal joint to a short, vertical shaft mounted on the chain link in question and carrying a horizontal, circular disc. Said disc can be caused to turn by passing along an actuating rail inserted in the path of movement at a selected discharge station along the transport path which turning is transferred through the vertical shaft and the uni¬ versal joint to the oblique pivot shaft carrying the transport tray at the top. The corresponding turning of said tray will cause the tray to tilt laterally and hence to discharge a transported object resting on the tray at the particular place.

Here a relatively simply controlled tilting of the tray is involved, the desired tilting being caused ex¬ clusively by turning of the oblique pivot shaft fixedly connected to the tray, whereas otherwise it is customary to use substantially more complicated tilting devices for a purely lateral tilting of the trays.

However, in connection with the present invention it has been realized that the structure mentioned above may be made still substantially simpler and cheaper, viz. by omission of the universal joint and the vertical shaft. The oblique pivot shaft may be supported merely by a correspondingly oblique bearing member on the chain link, when provision is made for mounting said means for turning out the shaft directly thereon; truly the turn¬ ing of said means will not take place in a horizontal plane, but about the oblique axis, which, however, in no way constitutes an obstacle to a good efficiency of said masses. In so far a circular disc may still be involved, which very well can be caused to turn by horizontal pas¬ sage along an actuating rail, even if the disc occupies an oblique position.

On this background the present invention is charac¬ terized by the features stated in the characterizing portion of claim 1.

Of course, an essential simplification is that the mentioned universal joints in the many trays of a sort¬ ing conveyor can be dispensed with, but in the structure of the invention a further simplification can be ob¬ tained in that the pivot shaft may consist of a tube, which is rotatably received on a fixed stub shaft ex¬ tending obliquely upwards from the chain link, whereby said fixed stub can constitute all of the necessary bearing equipment, cf. claim 2.

Generally it is desirable that the trays are se¬ cured against inadvertent lateral tilting from their horizontal position during the transport from the rele¬ vant area of discharge, which is easily attainable ac¬ cording to a feature of the invention, cf. claim 5.

The invention will be explained in more detail in the following with reference to the drawings, in which:-

Figs. 1-3 illustrate an embodiment of the sorting conveyor according to the invention.

Fig. 4 a modified embodiment, and

Figs. 5 and 6 further details of the conveyor.

The conveyor shown in Figs. 1-3 comprises an end¬ less feed chain 2 serving to support and advance a se¬ ries of transport trays 4, here shown as round discs, which, however, they do not necessarily have to be. These trays are, in a manner well known in principle, individually tiltable to both sides, so that a transport object resting on a plate 4 can be caused to be dis¬ charged anywhere along the conveyor by lateral tilting of the plate when passing the position in question. The invention is concerned with the particular way in which the plates are mounted on the chain 2 in order that said tilting operation may be performed as simply as pos¬ sible.

Each tray plate is below its control area fixedly mounted in a horizontal normal position on the upper end of a pipe 6, which extends obliquely downwards towards the claim 2, i.e. slanting in the vertical plane through the chain, and which pipe is received on a stub shaft 8, the lower end of which is firmly connected to the chain 2. The shaft 8 and the pipe 6 extend upwardly and for- wardly or upwardly and rearwardly in the feed direction of the chain, preferably at an angle of about 60° with a horizontal plane. As shown in Fig. 2 the assembly 4,6, which is rotatably mounted on the shaft 8, is supported by a ball 10, which is placed in the pipe 6 and rests against the upper end of the shaft 8. Secured to the outer side of a lower portion of the pipe 6 is a trans¬ verse plate 12 having a triangular shape such that it presents a pair of oppositely extending end portions 14 and a forwardly extending end portion 16, of which the latter is connected to a tension spring 18, the other end of which is fastened to the chain 2 at some distance ahead of the plate 12. In Fig. 1 the plate 12 is shown to be parallel with the tray plate 4, thus in an oblique position with relation to the pipe 6, but actually it might very well be placed at right angles to the pipe 6.

The spring 18 will normally hold the pipe in such a position on the shaft 8, that the tray plate 4 is just horizontal, but the laterally extending plate ends or corners 14 can be caused to move against actuating mem¬ bers 20, which at the individual receiving stations along the conveyor are shiftable into a position, in which they will be hit by the plate corner 14 of the next passing tray assembly 4,6,8, so that the pipe 6 of said assembly will be turned, because the plate corner 14 in question is temporarily braked. This is in so far a conventional manner of actuation of the tilting mecha¬ nism for the tray plates 4, but in the shown arrangement this actuation will result only in a movement of one single member, i.e. the member 12,6,4, which is affected to turn about the shaft 8, as long as the corner portion 14 passes along the actuating member 20.

This turning will cause the plate 4 to turn some angle, but due to its oblique position with relation to the pipe 6 it will furthermore be moved so as to careen relatively to horizontal, as its opposite foremost and rearmost areas will be swung in the directions indicated by stippled arrows in Fig. 2. As a result the actuated tray plate 4 will careen to a laterally tilted position as shown for a single element in Fig. 3; this careening will take place to one side or the other all according to the actuating member 20 appearing at the correspond¬ ing other or one side of the chain 2.

With regard to discharge of a transport object from such a laterally tilted plate 4 it is actually of no importance that during the tilting out the plate turns some angle together with the rotated pipe 6, as the slipping of the object along the plate is in principle independent of the position of rotation of the plate. The plane of the plate will be laterally tilted, and when only this tilting is sufficient for the transport object to slip down along the plate, normally at tilting down to an angle of 30-45° with horizontal, the object will be delivered by slipping down, irrespective of how the plate might have rotated simultaneously.

When the actual tray plate 4 leaves the actuating member 2D, the spring 18 which has become tensioned by said turning out will turn the pipe 6 back to its normal position and hence also return the tray plate 4 to its horizontal normal position.

When the tray plate 4 is turned out, the supporting plane thereof will not be tilted exactly laterally, as in the tilted condition said supporting plane will in¬ tersect the horizontal plane through the chain 2 at a certain, small angle with the feed direction of the chain. However, this is in principle quite insignificant to the discharge operation, but it will imply that the objects will slip along the plates 4 with a certain velocity component in or opposite to the feed direction of the chain, which may be cultivated as an advantageous feature in the arrangement of the receiving stations.

In Fig. 4 it is shown that the tray plates 4 need not necessarily be centrally mounted on the oblique shaft pipes 6, as these may very well be connected to the plates at or even outside the periphery thereof, if suitable radial supporting areas extending from the plates 4 are used. Also in Fig. 4 a circular shape of the plates 4 is shown, which, however, can have other contour shapes.

It will be understood that the invention is not restricted to the shown embodiments; thus an obvious possibility is to exchange the pipe 6 and the shaft 8 so that the plate body 4 is secured to an oblique pin, projecting downwardly into a shaft pipe, which is rigid¬ ly connected to the chain 2. Likewise the actuating turning of the plates 4 may be executed in other ways, e.g. by actuating means mounted in connection with the very moved system. The spring 18 could be replaced by other locking means for making sure that the plates 4 will take up their normal horizontal supporting posi¬ tions when not affected by the actuating members 20. The actuating means 20,14 are not new per se, it being known to use quite corresponding means for actuating turning of control members for relevant tilting mechanisms, and furthermore said means can be adapted in many other ways, even such including active elements mounted in connection with the chain itself at the individual as¬ semblies 4,8.

In Figs. 5 and 6 a preferred embodiment of the transverse plates 12 on the shaft pipes 6 are shown. To said pipes an upper plate member 22 is secured, below which a second plate member 24 is mounted so as to be pivotal about the shaft pipe 6 between limits defined by upright pins 26 on the member 24, said pins being mov¬ able in short slots 28 in the member 22. The member 24 is provided with protruding side arms 30 carrying outer wheels 32, which during the advance of the chain may engage an actuating rail 20, cf. Fig. 1, and thereby be urged backwards to turn the member 24.

The plate member 22 is at the back provided with a notch 34 engaged by a locking pawl 36 projecting from a tilt body 38, which is tiltably mounted in a block 40 in fixed connection with the chain link in question. The tilt body 38 furthermore has an upwards directed arm 42, the upper end of which is connected to a tension spring 44, which extends forwards to a pin 46 protruding from the upper plate member 22. Hereby the pawl 36 will be held pressed into the notch 34, so that the plate member 22 and hence the shaft 6 kin a normal position will be prevented from being turned out.

The lower plate member 24 also extends to the pawl 36 and is provided with a notch 48 which, however, is shaped with strongly sloping edges. Consequently the initial result of a turning actuation of the plate mem¬ ber 24 at the engagement of one of the wheels 32 with an actuating rail 20 will be a slight turning, sufficiently however for the side edges of its notch 48 to press the pawl 34 out of the locking engagement with the notch 34 in the upper plate member 22, after which the further turning of the plate member 24 will cause the pins 26 to hit the ends of the slots 28 and thereby bring along the upper plate member 22 to turn the shaft pipe 6 and tilt the associated tray 4 laterally.

Thereafter the turning of the entire system can continue, until the tray is fully tilted out for execu¬ tion of the discharge. During the turning out the spring 44 is stretched, and it may be preferable that the system is temporarily locked in the extreme position, which may be done by means of the pawl 36, which will engage into a locking notch 50 near an outer stop nose 52 on the plate 22; such a locking will prevent the system from "springing back" at stopping of the turning out, which will allow the turning out to take place quite rapidly. Thus all of the tilted trays will be held in their respective oblique positions and must, of course, be returned to horizontal, before they again pass a feeding station belonging to the system; this may be accomplished in a simple manner by making the units prior to the arrival at the feeding station pass a fixed piece of rail, which presses a roller 54 mounted on an arm 56 protruding from the tilt body 38 upwards, whereby the tilt body 38 will be pivoted back and carry the pawl 36 out of engagement with the locking notch 50. The spring 44 returns the system to its normal position.

Claims

C L I M S :

1. A sorting conveyor having laterally tiltable transport trays, each of which is held on a tilt support on a conveyor chain, each tray being rigidly connected to a pivot shaft slanting obliquely downwardly and for- wardly or rearwardly in the length direction of the chain, said pivot shaft being rotatably secured to cor¬ respondingly slanting, fixed bearing members on the chain and connected to means for selective rotation of said pivot shaft for combined turning and laterally tilting of the tray during its passing of a selected discharge station, characterized in that said turning out means comprises arm portions extending outwardly to one or two opposite sides from and mounted in direct connection with said shaft for turning about the axis thereof on engagement with an actuation member extending into the path of movement of the respective arm portion.

2. A conveyor according to claim 1, characterized in that said shaft is a pipe, the lower portion of which is received on a stub shaft extending upwards from the chain.

3. A conveyor according to claim 2, characterized in that the stub shaftβ in the shaft tube extends to a level close to the upper, closed end of the shaft pipe, and that said end rests against the end of the stub shaft through a supporting member, preferably a ball, interposed between said ends.

4. A conveyor according to claim 1, characterized in that the pivot shafts are fastened to the transport trays eccentrically with relation thereto.

5. A conveyor according to claim 1, characterized in that the turning out arms are mounted on the pivot shaft with an ability to turn slightly with relation thereto, and that a locking disc or arm is firmly mounted on the shaft, said locking disc or arm in the horizontal position of the transport tray being in lock¬ ing engagement with a locking pawl pivotally mounted on the tilt support, the turning out arms being connected to a cam body, which during an initial turning of said arm portions first cooperates with the locking pawl to release said pawl from locking engagement with the lock¬ ing disc or arm and thereafter carries along said lock¬ ing disc or arm and hence the pivot shaft for turning out thereof.